If you think HIV is a nasty virus, then wait to you hear about the “Phoenix virus,” a fossil virus that has been dormant in the human genome. The retrovirus infected hominins Phoenix Virusfor millions of years, and while this isn’t exactly anthropological in nature, this study does help us understand selective pressures of the past that helped us get to where we are now.

Retrovirii work by infecting the host cell with an RNA genome that is reverse transcribed into our own nuclear genome. At which point our cells could manufacture the components of the virus. The image to your right is an electron microscopy picture of how the Phoenix virus, when infecting human cells, forms particles at the cell membrane. Should a population of early human ancestors been seriously inflicted by this virus, then survivors would have a copy however would not have been infected to the point of dying. Offspring could then have a copy of the viral genome within their nuclear genome.

A French team decided to study the Phoenix virus and was led by Thierry Heidmann at the Institut Gustave Roussy. He decided to try to awaken the ancestor of an entire family of HERVs called HERV-K(HML2). And,

“to “correct” for mutations, the researchers took dozens of known HERV-K(HML2) sequences and aligned them to create a so-called “consensus” sequence. Then they converted this information into a complete viral genome.”

He and his team showed that the newly crated virus could infect a variety of human cell lines and replicate. But its infectivity was extremely low, perhaps because human cells have evolved resistance against such viral invaders. Thanks to John Hawks and Boing Boing.